How Does Blood Work?
Over half the blood in your body is plasma, which is the liquid part of your blood. It is made up of water, salts, fat, sugar and proteins. Plasma is what carries blood through the body and works to transport nutrients, carbon dioxide and other waste products, antibodies, clotting proteins, chemical messengers such as hormones, and proteins that help maintain the body’s fluid balance.
The other solid part of your blood contains red blood cells, white blood cells, and platelets.
Red blood cells deliver oxygen from your lungs to your tissues and organs.
White blood cells are an important part of the body’s immune system and help to protect the body from infection.
Platelets help to control bleeding by working with proteins called clotting factors.
When any one of these components of your blood doesn’t work, it can cause impaired function that can lead to many types of diseases, including cancer.
Why Do I Need So Many Blood Tests?
This is one of the most common questions we receive from patients. Blood tests can tell your doctor important information about your health. For example, a complete blood count (CBC) will indicate if your blood shows any signs of infection, immune system problems, bleeding problems, and anemia (low iron). If a blood chemistry panel is ordered, it will provide important information to your hematologist about your heart and other organs, your bones and muscles. This test also checks levels of blood sugar, calcium and other minerals in your blood and checks for levels of dehydration.
For cancer patients, hematologists/oncologists use blood tests to help diagnose cancer and monitor a patient’s blood counts and vital organs before and during their cancer treatment. Identifying specific tumor markers that can be detected in blood can aid in individualizing treatment, monitoring the status of the disease, and sometimes detect genetic abnormalities.
The Importance of Blood Tests
You might be surprised to learn how much your doctor can tell about your health from a blood test. A blood test can give information on how well your organs are functioning, such as the kidneys, liver, thyroid and heart. It can also be used to help diagnose diseases or conditions such as coronary heart disease, anemia, diabetes, HIV/AIDS and cancer. A blood test can also check to see if you have certain risk factors for heart disease. The information your doctor gets from a blood test that will show whether medicines you are taking are working and will also assess how well your blood is clotting. While doctors cannot diagnose all diseases or medical problems with just a blood test, it’s one of the single most important tests to help your doctor address any current or future health problems you may have.
Common types of blood tests that your doctor might order include:
Doctors recommend that routine blood tests be done at least once a year. The risks of routine blood tests are low. Some people experience pain or discomfort from the needle puncture. Fainting from blood loss or a vein puncture can also happen. Blood tests are an important way for your doctor to determine your overall health. They can identify illness or disease in the early stages and help your doctor know how you are responding to treatments. Overall, the benefits of routine blood tests far outweigh the risks.